Gene-based vaccines (both plasmid- and vector-based) are considered a most promising approach for making both prophylactic and therapeutic vaccines against a number of infectious diseases and cancer. These vaccines can induce the cytolytic T cell responses thought to be critical for many viral and parasitic diseases and cancer more effectively than protein-based or killed-organism vaccines, yet do not have the potential risk that attenuated viruses must have. In addition, they may have a number of other technological advantages for vaccines needed on a global scale. They have likewise been utilized as tools to study fundamental immunological questions such as mechanisms of antigen processing and presentation, the interactions of the innate and adaptive immune systems, and the role of humoral vs. cellular immunity. However, a number of fundamental issues need to be addressed in order to fully exploit the potential of these vaccines, including increasing the potency of the vaccines by understanding the mechanisms of DNA uptake and antigen presentation, and determining how to harness the unexpected immunostimulatory effects of DNA itself, and understanding the mechanisms for the increased efficacy of the combined use of different gene-based vaccines. This meeting will provide a unique forum that attracts and is designed to promote the maximal multi-disciplinary interactions at various stages of research, that is, ranging from fundamental cell biology and immunology, to infectious disease and clinical trials that have been more focused on regulatory aspects of the clinical development of these vaccines, or upon the applications, this meeting will provide the opportunity to bring together scientists from a variety of fields (microbiology, virology, cell biology, vaccinology, gene therapy, oncology, infectious diseases, polymer chemistry) to address the fundamental cellular mechanisms involved, yet within the greater context of the vaccines and therapeutics.